Air-heating apparatus for furnaces



4 sheets-sheat 1 l (No Model.)

W. STUBBLBBINB. AIR .HEATING APPARATUS FR FURNACES.

,Patented Dec. 22,1896.

4 Sheets-Sheet 2.

W. STUBBLEBINE. AIR HEATING APPARATUS FOR FURNAGES.-

No. 573,799. Patented Dec. 22, 1896.

(No Model.)

(No Model.) 4 Sheets-Sheet 4. W. STUBBLEBINE.

AIR HEATING APPARATUS POR PURNAGES. v

No. 573.799. Patented Deo. 22, 1`896.v

UNITED STATES PATENT EEICE.

IYILLIAM STBBLEBINE, OF BE'IHLEHEM, PENNSYLVANIA.

AIR-HEATING APPARATUS FOR FURNACES.

SPECIFICATION forming part cf Letters Patent No. 573,799, dated December 22, 1896.

Y Application filed March 11,1896. Serial No. 582,807. (No model.)

To @ZZ whom it may concern,.-

Be it known that I, VILLIAM STUBBLE- BINE, a citizen ot' the -United States, residing at Bethlehem, in the county of Northampton and State of Pennsylvania, have invented certain new and useful Improvements in Air-Heating Apparatus for Furnaces; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to regenerative and reverberatory furnaces largely used in the manufacture of iron or steel, although the improvements are applicable to, and susceptible of use in connection with, blast-furnaces generally Where it is desirable to heat the air before forcing the same into the grate-chamber 0r Working chamber of the furnace.

In the erection of the common metal-working furnaces it has been the general, although not the exclusive, custom to place the airheating or regenerating appliances under the ground-line or in some part of the furnace Whichis not readily accessible for repairs and cleaning. This requires considerable tearing out of the furnace to have access to the airheating appliances for repair and other purposes, thus involving time and expense.

It is my purpose to provide a simple and comparatively inexpensive Which is readily accessible for purposes of repairs and in Which the air-blast may be heated to the proper temperature in an economical and expeditious manner. a

In the preferred embodiment or construction of my air-heater I employ metallic baseplates which are protected from the action of heat by refractory or fireproof slabs or blocks, and into these metallic base-plates are secured the ends of metallic heating-pipes arranged to conduct the air-blast from the lower compartment to the upper hot-air compartment. Each metallic air-heating pipe is protected from the deteriorating influence of the high heat or temperature in the middle compartment by refractory tiles, which are placed over and around said metallic pipes or tubes so as to rest or be superimposed one on top of the other, yand said tiles are coupled together by interlocking joints.

My invention further consists in the novel construction K combination and con struction of parts, which -Will be hereinafter fully described and claimed.

To enable others to understand my in vention, I have illustrated thesame in the accompanying drawings, forming a part of this specification, and in whichplanes indicated by the dotted lines 4 4, 5 5,

'and 6 6 through a regenerative furnace having my air-heating appliances embodied therein. Figs. 7 and 8 are respectively a perspective View and a sectional elevation th rough one of the air-heating pipes and the tiles for protecting the metallic pipe or tube. Figs. 9 and l() are respectively a perspective and a sectional elevation of another form of the air-heating pipe and tiles therefor. Figs. l1 and l2 are detail perspective Views of the tiles shown by Figs. 7, 8, 9, and l0, respectively.

Like letters of reference denote corresponding parts in all Vthe figures of the drawings.

A designates the Working chamber of an ordinary furnace.

B is the combustion or grate chamber, and C is the stack or uptake.

In the construction of the furnace to accommodate my improved air-heater for the blast from the blast pipe or pipes C' C the rear or back wall D to the chamber A is constructed with a vertical air-heating chamber vor chambers E E.

In the embodiment of the invention in the reverberatory furnace shown by Figs. 1, 2, and 3 the air-heating chambers E E are divided by the uptake or stack C, thus forming two chambers, which are situated on opposite sides of the stack or uptake, and these chambers E E communicate With the Working chamber A through the medium of the Sev IOC)

inlet openings or passages F F, which are formed in `the walls d, that separate the chambers E E from the working chamber A. Said chambers E E also communicate with the uptake or stack C by the flues or passages F' F', formed in the walls CZ' d' of the stack, and these outlet passages or tlues F' F' are located some distance above the inlet passages or openings F F, whereby a part of the heat froml the working chamber A is caused to circulate around and through the chambers E E before it escapes from the chambers E E into the uptake or stack.

Each heating-chamber E E is divided into the three compartments or subchambers c e' e2 by means of the horizontal walls G G', one of which walls G is provided near the lower part of the chamber E below the intake-passage F, while the other wall G' is arranged near the top of the chamber E and at a suitable distance above the outlet-passage F' from said chamber E. The middle compartment or subchamber c' is much deeper than either the upper or lower compartments or subchambers e e2, and through the deep middle compartment e.' passes the series of airheating pipes or tubes H H', which are protected by the refractorT tiles I I' I2, as will be hereinafter more fully described,

The division wall or oor G in each chamber E is composed or laid of fire-brick or refractory tiling in one, two, or three courses,

and this iire-brick floor is laid on and supported in a suitable way within the chamber E to leave the lower subcompartment e free and unobstructed for the passage of the airblast to and through the heating-flu es formed by the pipes and refractory tiles. The blast pipes C' C' discharge into the subcompartments e e of the chambers E E in a suitable way, or said pipes may discharge into boxes c, (shown by Fig. 2,) from which the blast is delivered to the series of tubes.

Below the wall or floor G in each chamber E is secured one or more metallic base-plates J, which have threaded holes produced therein, and in these holes of the metallic plate or plates J are screwed the lower threaded ends of Athe metallic heating-pipes H H', the lower ends of which are open for the free and unobstructed passage of the air-blast to the pipes or tubes H H'. These pipes or tubes pass through the hre-brick floor G and through the deep middle compartment e' and through openings in the upper division-wall or roof G', whereby the pipes take the blast of air from the lower compartment e, conduct the Ysame through 4the middle compartment e', and deliver it to t-he upper compartment c2, the air-blast being heated by contact with the hot pipes or tubes. These pipes or tubes are made of metal to afford a good heating surface or medium for quicklyheating the air-blast during its passage through the tubes or pipes, and said tubes if left unprotected would rapidly deteriorate under the iniiuence of the high temperature of the compartments e', which communicate directly with the working chamberA through the inlet-passages F. To protect the metallic tubes against the action of the heat, I provide the incasing tiles I I' I2 for each tube. These tiles are made of fire-resisting refractory material, suitably molded and harden ed before setting them around the metallic tube or .pipe, and each tile, except the bottom tile of the series, is provided at one end with a contracted nipple i, and at its other end with an internal groove or recess i', forming a seat to receive a nipple 4on an adjacent tile. After each metal tube or pipe has been screwed into the metallic base-plate J the bottom tile I is slipped over the tube or pipe and its lower solid or ungrooved end is fitted in a groove or recess i2, produced in top layer or course of the wall or Hoor G. The

next tile I'is placed over the tube so that ther nipple 'i on the lower tile fits in the seat t" of the tile I', and the two tiles abut solidly or squarely together. then placed in position with the nipples fitting in the seats of adjoining tiles until the top tile I2 is reached, whereupon the tile I2 is adjusted to have its nipple z' iit tightly in the roof or crown G' of the compartment e of the chamber E. It will thus be seen that each tube H or H'is thoroughly protected against the heat by the incasing stack or series of tiles, which are superimposed one on top of the other and are coupled together by interlocking joints. The interlocking ends of the tiles may be united together by cement or in The succeeding tiles are IOO any other suitable way, if desired, as will be I the tiles in place when they are stacked and properly adjusted in the heating-chamber.

The top wall or roof G' in each chamber E is supported by the walls of the chamber E in any suitable way, and this roof G may consist of lire-brick or metal, or both, which may be let into the walls of the chamber E.

The heated air-blast from the series of pipes H H' is delivered into the chamber e', andit is conducted from thence to the working chamber A through the side flues K, `which have ports 7e, that open into said workin g chamber, as shown by Figs. l and 2.

The operation of the furnace shown by Figs. l, 2, and 3 is simple and rea-dilyunderstood from the foregoing description, taken in connection with the drawings. Vhen the furnace is in operation, a part of the heat from the working chamber A passes into the compartments e' through the inlet-passages F, and the remaining heat from said chamber A escapes through the arched opening b into` i the stack C. The heat admitted to lthe comair-blast from theblast-pipes c c' is delivered to the subcham'bers e e of the chambers E E, passes through the 'tile-protected pipes or tubes H H', is delivered into the upper chambers e262, and thence passes through the fines and ports K k into the working chamber A.

In the embodiment of my invention in a regenerative gas-furnace (shown by Figs. `4f, 5, and 6) the rear wall of the furnace is constructed with a single transverse air-heating chamber E, which extends the full width of the furnace, as shown by Fig. 5, and which is situated between the working chamber A and the stack or uptake C. This single transverse chamber E communicates with the working chamber by means of the two inletpassages F F, produced in the wall clnear the side walls of the furnace, (see Fig. 5,) and said chamber E is connected to the stack C by a single central outlet-passage F', that is arranged on a plane some distance above the inlet-passages F F, so that the heat fromthe working chamber is caused to sweep within or circulate through the chamber E before the heat escapes through the outlet-passage F'to the stack. This single transverse chamber E in the regenerative furnace is divided into the three compartments e @'62 by the two division-walls G G', or, as they may be termed, the iioor G and the roof G', and the deep middle compartment e' of this chamber E connects by the passages F, F, and F with the working chamber A and the stack C, respectively, as shown.

The floor Gconsists of two or more courses of fire-brick or tiles let into the walls d CZ' of the chamber E, and it rests on the intermediate pillars or arches cl2, erected in the lower subchamber e. To the lower side of this floor G are applied the metallic base-plates J, which receive the lower threaded ends of the metal pipes or tubes H lI-I', that pass through the floor G, the compartment e', and the roof G', and said pipes or tubes H H' are protected by the refractory tiles I I' I2, constructed and arranged in the manner shown and described in connection with the reverberatory furnace illustrated by Figs. 1 to 3, inclusive.

The blast pipe or pipes C C' discharge the air-blast into the lower chamber e below the bed of the working chamber A, and the blast passes through the tile-incased pipes H H' and into the upper compartment e2 of the chamberE, the blast being heated during its passage throughthe pipes or tubes H H'.

The combustion or grate chamber B at the front of the furnace has a bridge-wall b between the grate and chamber A, and on the front of the furnace is the gas-supply pipe M, having the nipples my, which discharge into the combustion-chamber B. The roofN of the furnace is curved down or deflected over the combustion-chamber, as at n, and in this deflected part n of the furnace-roof are the airinlet openings n'. In each side of the furnace are provided two longitudinal lues O O', and

across the front part of the `roof N, above the deflected part n, is'an air-chamberrN', which delivers air to the openings n'. The two outside iiues O O on the sides of the furnace connect at their rear ends with the upper nect with the upper compartments `e2 e2 of the' chamber E, and these iiues O' O'A (which lie within the iiues O O) have ports or openings 02, which extend inwardly from the flues and open into the chamber A through the side walls of the furnace. In these side iiues O O' are provided the valves or dampers PP', having suitable handles, which extend outside of the furnace, so that either of the valves may be operated to close the lues and shut off the air from passing either to the workin g chamber A or the combustion-chamber B.

In the application of the tubes or pipes H H' in the single transverse chamber E of the regenerative furnace shown byFigs. 4to G, inclusive, the tubes are arranged in sets, and one plate J is provided for each set of tubes. As shown by Fig. 6, a series of these plates J is provided, and a set of four tubes or pipes Y H H' is attached to each plate, although the number of tubes to each plate may be increased or diminished. The plates J and the sets of air tubes or pipes are arranged in series in the direction of the length and width of the chamber E, whereby a large number of air-heating tubes are compactly arranged within said transverse chamber to secure a large surface or area for heating the air-blast.

It will be observed that the metal baseplates, to which the tubes have their lower ends attached, are protected by the refractory wall or floor G from the effect of the heat in the compartment e' of the heating-chamber and that either of these plates J may be removed when the set of lues HH' has been removed therefrom.

The metallic tube H or II' can be easily removed with or without disturbing the stack or superimposed refractory tiles I I' I2, which are attached to the walls or the floor and roof G G', because these tubes are readily accessible.

The operation of the regenerative furnace shown by Figs. i to 6, inclusive, is readilyr understood. When the furnace is in operation, gas is supplied from the pipe O to the combustion-chamber, and the air-blast is forced into the subchamber e from the blast pipe or pipes at the rear end of the furnace. The blast is heated as it passes through the tubes H H', and the hot air is conducted bythe side flues O O', which iiues O' discharge the heated air into the working chamber A, while the lues O deliver the hot air to the chamber N', from whence the air passes through the ports n' into the combustion-chamberB. The

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heated air from the rear end of the working chamber A passes through the passages F F into the middle compartment c of the chamber E, and it circulates around and in contact with the tile-incased tubes or pipes HH beforevit escapes through the exitfpassage F into the stack C, whereby the pipes or tubes H H are heated to the high temperature necessary to heat the air-blast as it passes through the pipes H H'.

The tiles which incase each pipe or tube H or H' may be made of cylindrical, square, or

any other desired form.

I am aware that changes in the form and proportion of parts and in the details of construction of the embodiment of my invention herein shown and described may be made by a skilled mechanic Without departing from the spirit or sacrificing the advantages of the invention, and I therefore reserve the right to make such modifications and alterations as fairly fall within the scope of the invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

l. In a furnace, the combination of a heating-chamber, the series of protective tiles extending across said chamber and each stack of tiles extendi ng into the opposite walls thereof, andv a metallic tube extending through each stack of tiles and removable therefrom without disturbing said stack, as and for the purposes described.

2. In a furnace, thecombination with a heating-chamber, of the interlocking tiles arranged end to end and extending across said heating-chamber, and heating pipes or tubes removably fitted in said series of tiles, substantially as described.

- 3. In a furnace, the combination with a heating-chamber, of the series of superimposed interlocked tiles extending into the walls of the chamber, and removable pipes or tubes fittedl within each stack of tilesand detachably fastened in place at one end, substantially as described.

4. In a furnace, the combination with aA heating-chamber, of plates on the bottom of said chamber, blast-heating tubes or pipes detachably fastened to said plates, and a sectional refractory casng for each tube or pipe, substantially as described.

5. In a furnace, the combination with a heating-chamber 'having the floor and roof G, G', of a series of plates protected bythe floor from the heat in the chamber, sets of blast-heating pipes or tubes extending from the oor to the roof, and each set of pipes fastened det-acliably to one of said plates, and the interlocking tiles which incase the pipes or tubes and are joined to the floor and roof of said chamber, substantially as and for the purposes described.

6. In a furnace, a divided chamber in the rear wall, having one compartment connected to the furnace-chamber and to the stack or uptake and having a floor G and the roof G which forms the lower and upper air-chambers e', e2, combined with the removable blastheating pipes or tubes extending across the lieatingchamber and secured in the oor and roof thereof to communicate with the airchambers e, e2, and the refractory interlocked tiles which inclose the tubes or pipes and are extending into the floor and roof of said heating-chamber, substantialiy as and for the purposes described.

In testimony whereof I aix my signature in presence of two witnesses.

WILLIAM STUBBLEBINE.

IVitnesses:

W'M. H. SCOTT, GEO. L. BAUM. 

